Field of the Invention
The disclosure is related to a battery, and in particular to a battery with a soaking plate for a thermally and electrically conductive channel.
Description of Related Art
Batteries are installed in various products on the market, from highly demanded portable electronic products to cars and motorcycles used for transportation. A goal constantly pursued by those in the industry is how to reduce battery manufacturing costs and provide consumers with safe and high quality batteries.
Lithium batteries are widely used due to their high power (output) and high energy density. Generally, a lithium battery includes a roll formed by a positive electrode layer, an insulation layer, and a negative electrode layer. The insulation layer prevents the positive electrode layer and the negative electrode layer from directly contacting each other. The roll is housed in a battery container by way of stacking or winding, and after the battery container is filled with an electrolyte solution, the battery container is sealed. After the battery completes a formation step, it may be used as a battery.
When a lithium battery discharges, every spot in the roll releases heat, and since the insulation layer between the positive electrode layer and the negative electrode layer and between multiple stacks or winding of rolls is a heat insulator, it is difficult for heat inside the battery to be dissipated, and heat accumulates in large quantities in the rolls. Moreover, since substrates of the positive electrode layer and the negative electrode layer are electrically conductive materials, heat inside the battery is conducted through the positive electrode layer and the negative electrode layer and accumulates at a roll current convergence point. In general, in order to channel currents out from the battery and make the battery container easy to be sealed, the roll current convergence point is usually disposed in the center of the battery. A great amount of heat hence accumulates at the center of the battery, causing an uneven distribution of temperature in the battery. The result is that internal temperatures of the battery continue to rise, meaning that a chance of thermal runaway increases. Once thermal runaway occurs in the battery, an eventual result may be explosion of the battery.
In the prior art related to heat dissipation of batteries, a heat guiding layer or heat dissipation fins are mainly disposed on an outer battery shell to dissipate heat away from the battery. However, even if heat outside the battery shell is removed, the uneven temperature distribution inside the battery cannot be prevented, nor can heat accumulation at the roll current convergence point be avoided.